A joystick is utilized to control a robot arm or a position of an object. That is, the position of the object or robot arm is controlled by moving the joystick. When an operator rotates the joystick, the rotated position of the joystick is detected to thereby allow the robot arm to be controlled by moving the robot arm in proportional to a movement distance of the joystick.
Korean Patent Laid-Open Publication No. 10-1994-0000955 discloses a joystick and a position detection method using the same, and Korean Patent Laid-Open Publication No. 10-1999-0061783 discloses a method of driving an object by operation of a joystick.
In the related art, in a case of controlling the object or the robot arm by moving the joystick, an operator may visually identify that an object comes into contact with another object so as to apply pressure thereto, but may not sense the same. Accordingly, when the operator continues to operate the joystick in a state of not visually identifying the same, pressure may be excessively applied to the robot arm. In this case, there is a problem in that the robot arm may be damaged due to an excessive load applied thereto.